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Patents in France

French patents are granted by the French Patent office after formal examination and establishment of a search report.


The French patent law defines two different types of protection for technical inventions, namely the patent of invention and the utility certificate.

The patent is granted for a duration of 20 years with a search report.

The utility certificate is granted for a duration of 6 years without search report.


A patent application shall be filed using the prescribed forms and conditions

a) Patent application

The patent application must contain a description of the invention and claims defining the scope of the protection. Drawings may be added for completing the description. The description and claims of the application as filed may be filed in any language. A French translation must be filed within three months.

The claims should normally be drafted in two parts with a preamble defining the generic object of the invention and comprising all technical features which, taken into combination, are already in the prior art, and a characterizing part stating the technical features which form the invention together with the features of the preamble.

Multiple dependent subclaims related to any preceding claim may be provided.

b) Authorization for disclosing and working the invention

For reasons of national defense, all applications filed in France for obtaining a French patent or certificate of utility or a European patent are submitted to an authorization issued by the French Patent Office before any disclosure or working of the invention. Except in cases where the invention is to be kept secret for national defense purposes, such an authorization is automatically issued within a maximum time of 5 months after filing of the application at the French Patent Office.

c) Formal examination

The French Patent Office examines all applications for patents and certificates of utility and may reject the application for the following formal reasons:

  • when the application contains more than one invention or several inventions which do not form a group of inventions sufficiently related together, thus leading to an objection for lack of unity;
  • when the claims do not define an invention, for example if the claims are only directed to an intellectual or mathematical method as such, a computer program as such or a purely intellectual activity as such;
  • when the invention relates to a method of therapeutical treatment or diagnostic for human beings or animals, such kind of inventions not being capable of industrial applicability;
  • when the claims are not fully supported by the description;
  • when contradictions arise between the description and the claims or between parts of the description.

In any case, the applicant will be given a possibility of filing arguments and amending the description and claims before final rejection of the application.

d) Disclosure of prior art

The French Patent Office requests the communication of any pertinent prior art cited abroad for all applications filed in France claiming the priority of a first application filed outside of France. Failure to answer to this request leads to rejection of the application.

d) Search report procedure

In order to obtain a patent of invention with a duration of 20 years, the applicant has to request establishment of a search report and to pay the corresponding fee at the filing of the application.

The French Patent Office issues a draft of search report on the basis of the pertinent references cited by the applicant. If no pertinent references are cited on this draft of search report, the applicant is not compelled to file any answer. He may however take this last opportunity for amending the claims of his application.

On the contrary, if pertinent references are cited on the draft of search report, the applicant is compelled to file an answer containing a technical argumentation and/or an amendment of the initially filed claims. Failing such an answer from the applicant, the French Patent Office will issue a notification giving a last possibility to the applicant for answering. Without any answer, the application is rejected.

The search report is issued together with a written opinion from the Examiner relating to the validity of the claims. Although the French Office has no possibility to reject an application for lack of inventive activity, the Applicant may thus have a first opinion as concerns novelty and inventive step of the invention.

The application may also be rejected if the examiner considers that the claims as maintained or as amended by the applicant define an invention clearly lacking novelty. A further opportunity is then given to the applicant to further amend the claims of his application.

e) Grounds for rejection by the Examiner

A patent application may be rejected on the basis of the following grounds:

  • the applicant fails to divide his application notwithstanding a lack of unity objection from the examiner;
  • a divisional application contains new matter;
  • the invention is excluded from patentability because it is against the public order, against the morality or because it is directed to a part of the human body as such or a gene structure as such or to plant or animal varieties or essentially biological processes for the production of plants or animals (microbiological processes and products thereof are allowable);
  • there is clearly no invention claimed as such. It is the case of discoveries, mathematical methods, aesthetic shapes, methods in the course of intellectual or business activities, computer program or presentations of information;
  • the invention is unclear so that the novelty search cannot be made;
  • no amendment in the claims has been made after an objection of lack of novelty;
  • the claims are not supported by the description;
  • no answer has been filed after receipt of a draft search report citing relevant references.

f) Grant of the patent

After the applicant has answered to the draft of search report and also possibly to observations filed by third parties after publication of the application, the French Patent Office issues a notification requesting the applicant to pay an issue fee.

Upon payment of such a fee, the patent is finally granted together with the search report prepared by the French Patent Office on the basis of the draft of search report and the answer of the applicant.


A patent can be granted for one invention only. In reply to a notification from the French Office or on its own volition the applicant may divide his application.

Unity of invention is recognized in the following situations:

  • in the case of a product invention, when the application contains claims directed to the product, a manufacturing process of the product and a use of the product or when the application contains claims directed to the product, a manufacturing process of the product and a machine used in the process ;
  • in the case of a process invention when the application contains claims directed to the process and a machine used during the process.

If the French Patent Office considers during formal examination that there is no unity of invention,the application may be rejected if the applicant does not limit the claims as mentioned above.

The applicant is given a prescribed time limit to file corresponding divisional applications keeping the filing date of the original application.

Independently from such an objection of the Patent Office, the applicant has always the possibility of deciding for himself to divide his application and file corresponding divisional applications as long as payment of the granting fee has not been made.

In filing divisional applications, it is possible to maintain the original description in all divisional applications.


The right to the patent belongs in France to the true inventor. However, the applicant is deemed without contrary evidence to be the true inventor.

a) Co-ownership

The French patent law defines rules of co-ownership when an application is filed by several persons. These rules are not compulsory and a different organization may be prefered by the parties who can execute among themselves a co-ownership agreement with different provisions.

The provisions of the law in the absence of such an agreement are the following:

  • each co-owner may use the invention without the authorization of the other co-owners. However, he must indemnify the other co-owners who are not using the invention;
  • each co-owner may file an infringement action alone before the Courts as long as he has informed the other co-owners beforehand;
  • each co-owner may conclude a non-exclusive licence as long as he provides for a suitable indemnification of the other co-owners. However, the draft of the agreement must first be communicated to the other co-owners together with an offer to those co-owners of assignment of the co-ownership portion;
  • no exclusive licence may be concluded without any formal authorization of all the co-owners;
  • the co-owners have a prior assignment right preference in case of partial assignment.

b) Employee’s invention

The French patent law contains provisions for employee’s inventions.

Inventions made by an employee performing an inventive task which effectively corresponds to his job belong to the employer. However, a specific reward corresponding to the real value of the invention must be paid to the employee.

All other inventions belong in principle to the employee. However, inventions made with the help of the employer’s facilities or which fall within the business area of the employer may be claimed by the employer. The employer may claim a part of the right to the patent covering the invention such as a co-ownership or a licence. The effective price corresponding to the value of the invention must be paid to the employee.

Disputes between employers and employee relating to those matters can be heard before a special Committee organized within the French Patent Office or before the Courts.

c) Claim for the propriety of an invention

The real proprietor of an invention, i.e. the real inventor or his successor in title, may claim the propriety of a patent which he feels should not have been filed. The claim is brought before the Courts within 3 years after grant of the patent. If the patent application is still pending, the delivery procedure may be deferred.


In order to maintain a patent or a certificate of utility in force in France, annual fees are to be paid each year at the French Patent Office.

a) Maintenance

The annual fees must be paid before the end of the month corresponding to the filing date of the application.

A further 6 months period is allowed to pay the fee together with a supplemental fee.

b) Restoration procedure

When a French patent or a European patent validated in France or a French patent application or certificate of utility, has lapsed for example after failure to pay an annual fee, restoration can be requested before the French Patent Office on the basis of a detailed explanation and evidence of a legitimate excuse for non payment.

The request for restoration must be filed within two months from the date or removal of the cause of lapse but at the latest within one year from the lapsing date.


The patentability requirements are the same in France in the case of a certificate of utility as compared to a patent.

A patent application may be converted in an application for certficate of utility, the contrary not being true.

A certificate of utility can be granted in France for any kind of invention including chemical producs, processes and methods.

The certificate of utility only differs from the French patent on the following points:

  • no search report is required for a certificate of utility;
  • the duration of the certificate of utility is only six years;
  • the claims of the application for a certificate of utility may be amended at any time before grant;
  • in the case of a litigation before the Court, the owner of the certificate of utility must produce to the Court a search report issued by the French Patent Office.


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